We propose to study key cellular events related to ACTH-action in rat adrenal cell suspensions derived from enzymic digestion of rat adrenals. These events involve 1) the binding of ACTH to plasma membrane receptors, 2) activation of plasma membrane adenyl cyclase and cyclic-AMP (CAMP) production, 3) activation of glycolysis and respiration by CAMP and 4) CAMP-initiated corticosteroidogenesis and release of corticosterone to the outside of the cell. The overall objectives of our studies are to understand the biochemical events occurring at the cellular level during activation of rat adrenocortical cells by ACTH. Comparative studies are also planned with cells derived from normal and abnormal adrenal tissue. Such studies may indicate important abnormalities in all or some of the aforementioned events in diseased cells and lead to a better understanding of the cause of certain diseases of the adrenal cortex.